Manufacture of tires



cta 28 1924. l 513 434 T. SLOPER MANUFACTURE OF' TIRES Filed Aug. 8,T922 A q w n #www N92/f4 i lv *im* Patented Get. 28, i924.

rarest erica. y

MANUFACTURE OF TIRES.

Application led August 8, 1922.' Serial'No. 580,434.

To alli/whom t ma/.e/ concern.'

Be it kno-Wn that l, THOMAS SLOPER, a subject of the King of England,residing at Devizes, Wiltshire, in England, have invented certain newand useful Improvements in the Manufacture of Tires, of Which thefollovvingis a specification.

This invention is for improvements in or relating to the manufacture. ofpneumatic tire-covers and has for its object to provide a process ofmanufacture whereby a tirecover made in the fiat or endless band form,and which When finished is` provided in each edge With an annularchannel containing a metal inextensible ring, can be removed from themould Whereon it is vulcanized Without having to 'collapse the mould,and can be altered in shape toqthat of a pneumatic tire-cover Whilstmaintaining the channels in such form that the rings in the finishedtire shall lie in the proper positions the-rein .and shall not bedistorted.

If a tire-cover is made and vulcanized inv the flat form With permanentinextensible `rings or- Wires in its edges it cannot be removed from themould Without collapsing the latter, and subsequent shaping of the tiretwists and distorts vthe inextensible rings so that ythey do not taketheirV proper position in the finished tire. c

The, process for manufacturing pneumatic tire-covers having inextensibleedges according to. this invention, consists in (a) building into eachedge-portion of the tire-band, Whilst it is in` the fiat form, aremovable core to fill the required channel composed of a ductilematerial, for example lead, which is such that the circumferentialdimensions of the core can be changed and/or the core deformed for `thepurpose hereinafter described, the channel being only provisionallyclosed along one side so that it can be afterwards opened to remove thecore; removing the said core after vulcanization on the mould; (c)substituting therefor an inextensible ring which is to remainpermanently in the tire, and (d) permanently closing the sides of thechannel `to retain the inextensible ring therein.

After the permanent inextensible ring has been introduced the open sidesof the channel can be sealed together by stitching or the like, With orWithout further vulcanization, and to enablev the stitching or likeprocess to be carried out an annular recess may be provided at the edgeofthe coverV in the outer surface toreceive the operativel part ofthestitching orA like machine so that the stitches or Vthe like `can extendfrom. the

inner face of .the .tire into the said recess.

A further feature of vthis invention con.- sists in providing aninextensi-ble ring for insertion in the edge portion of a tire, whichinextensible ring is composedof .a strip of metal, such as a steel band,Wound upon itself and secured against. unW-inding by any` sui-tablemeans.

rlhe invention is` more particularly de-K,

Figure. 4r is a section of the edge of a tireband in -Which theremovable core in Figure 3 has vbeen removed and replaced 'by aninextensible ring, the open sides of the channel being sealed bystaples, and

Figure 5 shows a section ofthe edge ofl a tire-bandalong the line l1%1,Figure ll.

Like reference-letters indicate like parts throughout the drawings.

The tire-band is made up in the flat in the usual Vmanner except thatvthechannel for the reception of the inextensible ring is filled vby acore A (Figures l and 3) of ductile material and the open sides,indicated by the line'B in the rsingle channel shown, are separated by amaterial Which will not vulcanize so as to permit of access,

to the channels after the tire has been shaped.

lf a separating piece of material is in.- serted in this manner the sideWill definitely remain open, but it Will be `appreciated thatl thearrangement might be such that the side should be temporarily closed insuch manner that it can be easily ripped apart and for the purpose ofYthis inventionthis. Would be considered ,an` open side.

When the tire-band has been made up and the tire has been pressed andvulcanized, the. core A is replaced by a permanent inextensible ring C(Figures 2 and a) of similar shape to the core A. and the material for'preventing the vulcanization of the open sides of the channel isremoved.

Whilst the tire-band is being made up and during the subsequent pressingand vulcani- Zation of the tire, the core A substantially retains itsoriginal shape and does not become distorted as would be the casev withan ineXtensible ring.

By the term ductile is to be understood any material which will deformin the manner required without losing its general form. ln other words,it must be such a material as can be compressed in a circumferentialdirection or in a radial direction without distorting it out of itscircular shape; such materials as lead, copper and even mildsteel may beused, although mildesteel is not desirable because it tends to bruisethe fabric of the band. Also a composition of rubber and canvas whereinthere is a preponderance of canvas fulfills the requirements.

After the core A has been replaced by the ineXtensible ring C the opensides of the channels are sealed in any suitable manner, for example bystitching, riveting, stapling or the like with or without vnlcanization.

To receive the stitching or the like there is provided on the externalsurface of each tire-bead an annular recess D which has one of its facesparallel to the inner face E of the tire. This recess provides a surfaceD1 which receives the operative part of the stitching or like machineused for sealing the open edges of the tire-band, the stitches or thelike extending from the inner face of the tire into the recess D, one ofsaid stitches being indicated by the letter F (Figure 2) and a stapleindicated by the letter F1 (Figures 4 and 5).

The inextensible ring C (Figure 2) is composed of a steel band C1 Woundupon itself and secured against unwinding by any suitable means.

The inextensible ring C (Figure 4.) may comprise any suitableinextensible members- C2 secured in a requisite packing material C3.

Generally the cross-section of the removable cores differs slightly fromthat of the permanent ineXtensible rings, due to the fact that thechannels alter in shape during the process of shaping the tire from theflat band to its proper tire shape.

lf an inextensible ring of special crosssection is required, theelements comprising the same can be shaped accordingly, for example withthe steel band C1 illustrated in Figure 2 it can have one side slopedtowards the other so that an inextensible ring is provided Whosecross-sectional shape resembles an oblong form with one side bevelled ltwill be appreciated that the deformable cores il., which areprovisionally inserted in the. channels in the tire-band, enable thetireband to be removed from the mould, whereon is vulcanized, withoutcollapsing the mould, the circumferential dimensions of the core can beslightly increased for removal purposes. 0n the other hand, those sainecores be decreased circumferentially during the pressing of the band onthe monld, and after vulcanization they can be deformed during theshaping process without serionsly affecting the shape of the channels inwhich they lie, so that these subsequently "ill, without difficulty,receive the permanent inextensible rings C.

ln some cases it may not be necessary to retain the deformable cores inthe channels during shaping, but these may be left tem- ?ierarilyen'ipty, or again, if temporary cores of circular cross-section areused, these may be removed before shaping and the final inextensiblering, also of circular cross-section, introduced, as these do not getout of place during the shaping operation.

rlhe invention is particularly applicable to the manufacture by the flatprocess of what are known as straight-sided tires which haveinextensible rings or wires in their edges.

FJ hat l claim as my invention and desire to secure by Letters Patent isl. A process for the manufacture of pneumatic tire-covers havinginextensible rings which consists of the following steps: (a.) buildinginto each edge portion of the tire-band whilst it is in the flat form, aremovable core to fill the required channel, composed of a ductilematerial which is such that the circumferential dimensions of the corecan be changed and the core deformed, the channel being onlyprovisionally closed along one side so that it can be afterwards openedto remove the core; (b) removing the said core after vulcanization onthe mould; (c) substituting therefor an inextensible ring which is toremain permanently in the tire; and permanently closing the sides of thechannel to retain the inextensible ring therein.

2. A process for the manufacture of pneumatic tire-covers havinginextensible rings which comprises the following steps; (a) building upa tire-band in the flat form with a channel in each edge-portion and anan nular recess formed in the outer face of the outer side wall of eachchannel, and lling each channel, whilst the tire-band is in the flatform, with a removable core composed of a ductile material which is suchthat the circumferential dimensions of the core can be changed and thecore deformed, each channel being only provisionally closed ing meansextending from the adjacent annular recess to and through that face ofthe tire-band which Will be the inner face of the 10 tire.

In testimony whereof I aiX my signature.

THOMAS SLOPER.

